Harbinger of R'lyeh

Lands your opponents control enter the
battlefield tapped.
Whenever a creature attacks you, you may pay {c}. If you do, create a 2/1 colorless Eldrazi Fish creature token.
Legends speak of a day when the darkest horrors from
the deepest depths of the world will rise to reclaim it.
The apostles of this faith reside in the sunken realm
known as R'lyeh